The present invention generally relates to the field of beverage dispensing machines, in particular, machines that can brew or extract coffee and coffee specialties such as cappuccino and the like or tea.
There is trend to propose beverage machines that are versatile enough to be able to deliver various coffee beverages such as espresso type coffee or coffee specialties such as cappuccino (coffee with a milk froth) or latte (coffee with liquid milk). Typically, those coffee beverages are received in beverage recipients, e.g., cups or glasses, of variable volume. For instance, an espresso coffee or ristretto is served in a small cup of about 40 mL, whereas a cappuccino can be served in a larger/taller cup or glass of from 110 mL to 250 mL. A long black coffee cup can also be served in a 110-mL cup. For cold coffee drinks, one also uses tall glasses.
The coffee beverages must also meet different quality attributes which are important. For instance, an espresso coffee must have a fine and stiff “crema” which is a stable emulsion formed by the oily compounds during extraction of the coffee product in the machine. The extraction process can be finely controlled to provide this crema, when the product is extracted from closed capsules, such as in the processes described in European patent applications 512,470, 604,615 and 870,457 and their US counterparts, U.S. Pat. Nos. 5,402,707, 5,649,472, 5,762,987 and 5,826,492.
With other coffee specialties, one may need to distribute a milk froth on top of the beverage such as with cappuccino-type beverages.
One problem is that due to the variable volumes of recipients for receiving the varied coffee beverages, the distance between the beverage outlet(s) and the recipient cannot be precisely guaranteed. In order for the machine to accommodate different size recipients, the distance between the outlet and the recipient is usually too high. Too high of a distance creates splashing issues.
Surprisingly, it has been found that an incorrect distance can also be detrimental to the quality of the “crema” or foam. For instance, if the distance between the coffee outlet and the recipient is too high, larger bubbles are formed in the coffee “crema”. Larger bubbles induce a “crema” which is less stable and less stiff. Therefore, there is a need for controlling and precisely adjusting the distance between the outlet and the recipient as a function of the recipient used in order to solve these hygiene and crema/foam quality problems.
There have been attempts for machines that have height-adjustable discharge outlets. For instance, in WO 2004/052159, the beverage outlet is borne by a height-adjustable slider. Therefore, a full beverage delivery block must be made moveable relative to stationary cups underneath. It is uneasy to make the beverage delivery moveable to an extent that encompasses a wide range of cup sizes. In particular, this complicates the construction of the machine when the machine comprises an extraction module for closed capsules because the module requires to be precisely closed about the capsule in a repetitive manner. The module must also be linked to a hot water line that needs to stand the repetitive height changes of the module. Furthermore, there is no indication how precise the height adjustment can be controlled in WO 2004/052159, which is also a problem because only containers of standardized shapes can so be used otherwise the quality of the beverage's foam cannot be guaranteed.
European patent application EP 0 585 607 relates to an espresso machine which comprises a support plate for the recipient that can be adjusted in height. The plate is supported on an appliance base with a collecting tray arranged therebetween which receives the surplus liquid and is detachably connected with the collecting tray. First of all, the adjustment of the support plate is merely mechanical and carried out by the user himself. Therefore, it cannot be controlled with all the precision and knowledge required. Secondly, the drip tray assembly raises hygienic problems because splashing is likely to occur on the support plate; and because the distance between the support plate and the drip tray increases for short cups of coffee, the liquid projections and dripping may not be well collected in the drip tray and the service area is likely to require frequent cleaning.
Therefore, there is a need for a beverage machine that can deliver a foamy beverage or beverage with “crema” with optimized foam/crema quality. There is also a need for a beverage machine that can deliver beverages from various recipient sizes without splashing issues. The present invention now satisfies these needs.